Leather-stretching device.



No. 696 ,7|6. Patented Apr. I, I902.

J. CALDWELL.

LEATHER STRETCHING DEVICE.

-(Application filed Mar. 26, 1900.) (No Model.)

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umo. wxsmncmu u c Nit arn'r muc JOHN OALDVVELL, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO THE W. S. NOTT COMPANY, OF MINNEAPOLIS, MINNESOTA, A CORPORATION.

LEATHER STRETCHINC-r DEVICE.

SPECIFICATION formingpart of Letters Patent No. 696,716, dated April 1, 1902.

Application filed March 26, 1900. Serial No. 10,128- (No modelh To (all whom it may concern:

Beitknown that I, JOHN CALDWELL, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Leather-Stretching Devices, of which the following is a specification.

My invention relates to devices employed in leather-stretching machines for stretching sides, backs, and other divisions of leather to prepare them for use in the manufacture of belting, and particularly to the class of machines which employ series of leather-holders, each holder being intended for engaging only a short portion of the leather margin.

The object of my present improvements is to simplify the construction of the holders and improve the means for connecting them to the appropriate part of the stretching-machine, whereby the holders are adapted to be more readily and conveniently connected and disconnected to the stretcher-head when desired.

The devices of my improvements, stated in a general way, consist of a series of separate bodies, each of which is provided with tines or other suitable means for engaging the leather on lines practically parallel with the edge of the portion of leather it engages, and a series of coupling devices, each of which is adapted to be detachably and pivotally connected to one of the holders, preferably at points thereon varying correspondingly with the inclination of the holder to the direction of tension of the leather, and means for adj ustin g and successively connecting the holders on a member of the stretching-machine. Such devices are illustrated in the accompanying drawings, in Which Figure 1 is a vertical longitudinal section of a portion of a stretching-machine,showing parts of a stretcher-frame and stretcherhead and one of my improved leather-holders in operative position on the head. Fig.

2 is a plan view, and Fig. 3 a side View, of such holder and a portion of its coupling device. Figs. 4 and 5 are similar views of a modified construction of the holder and coupling device. Fig. 6 is a plan view of another modification of the holder, and Fig. 7 is a plan view showing such holders in engage ment with portions of the irregular end of a strip of leather and their respective coupling devices connected to them.

In such drawings, 1 designates one of the two side pieces of an ordinary stretcherframe, which is so constructed as to support a side, back, or other division of leather during the operation of stretching it and afterward to be removed from the stretching-machine and still serve to support the leather, together with its holders, until the leather is dried and set and is ready for use. To this frame is secured a fixed head or member 2 for supporting one end of the leather and the holders which connect it to the frame, and a sliding head (not shown) is to be provided for supporting the other end of the leather and arranged to be connected to and operated. by a cross head or other moving part of a stretcher-machine. 'Whilemyimprovements are here shown in connection with the fixed head of the frame, it is obvious that they may with equally good results be employed in connection with the movable head or member.

The device shown for engaging the leather consists of a plate or body 3, the front por tion of which is provided with one or more rows of tines or sharp pins at, adapted to be forced through the leather by pounding or otherwise. In the rear portion of the body is a laterally-elongated curved slot 5, or a correspondingly-located series of holes 14 may be provided instead, forreceiving a hook or other suitable device for connecting such holderbody to a member of the stretching n1echanism. The object of such curved slot is to enable the connection to be made at such point as will bring the line of draft as near as practicable to the center of resistance offered by the tines when engaging a margin of leather at an inclination to such line of draft.

The means shown in Figs. 1, 2, and 3 for connecting the holder to the stretcher-head is a bar 6, provided with a hook 7 for engaging in the slot 5 and provided at its under side toward the rear with teeth 8 for engag ing correspondingteeth or serrations 9,formed on a plate 10 on the upper surface of the head 2. Such bars may be retained in engagement by a bar 11, that is pivoted or hinged to one ICO "z eeenie of the frame sides and arranged to swing or descend to the other side and be locked, and thus retain the tooth-bars in placeon the stretcher-head.

In the modification illustrated in Figs. at and 5 a series of studs or pins 12 is arranged in an arc in substitution for the slot 5, (shown in Fig. 2,) and the bar 6 is provided with an eye 13 instead of a hook at its end.

,In the modification shown in Fig. 6 a series of holes 14, arranged in an arc, is substituted for the curved slot 5. (Shown in Fig. 2.)

To prevent the end portion of the leather from rising while being stretched, a bar 18, hinged at one end to one of the side pieces and arranged to turn down to the other and be locked, may be employed. In advance of this bar is shown one of the usual movable bars 19, resting on the sides of the frame, which prevents the leather from sagging.

In practice in securing an irregular end of a strip of leather 17 that is laid on the frame each holder 3 is independently applied to the margin of the leather, preferably at about a right angle to the edge of the portion it is to hold and with its tines in line with and in engagement close to the edge of the-leather. All of the holders may be thus secured to the leather before the movable stretcher-head is operated and the coupling-bars 6 or equivalentdevices hooked or otherwise connected successively to the holders by means of the openings 5 or 14 or the pins 12 in their rear portions, and the coupling-bars may then be successively adjusted to proper parallel positions and made to engage the serrations on the stretcher-head. Thus there are provided simple and easily-handled devices for securing the leather margins in sections and for so connecting the separate holders to the stretcher mechanism that upon each holder the pull will be approximately equal at both sides of its connection and the tendency of the holder to twist or of the pinsto tear the leather or bend be obviated. As the holders are adapted to be readily connected in succession to the stretcher-head the machine may be started when only part of the holders have been connected, and others may then be connected and put in operation in succession as the condition of the leather may require. For instance, either or both of the outer holders (shown in Fig. 7) which engage the shorter and more yielding portions of the strip of leather may be connected to the head and operated before the intermediate holder or holders are connected and operated. In this way different longitudinal portions of the leather which differ in firmness or condition may be stretched in succession and to different degrees.

Patentable subject-matter herein disclosed and not claimed relative to the free pivotal connection of the holders to their coupling devices, enabling them to swing thereon under tension and relative to the means for connectin g the coupling devices to the stretcherhead, is reserved to be claimed in my pending application, Serial No. 1,421, filed January 15, 1900.

Having described my invention, what I claim is- 1. A leather-holder for a stretching-machine, consisting of a body provided with means for engaging the leather to hold it, in combination with a device for pivotally connecting the holder to apart of the stretching mechanism, said holder being provided with means for varying the point of its pivotal connection to the connecting device conformably to the direction of tension of the leather, substantially as set forth.

2. A leather-holder for a stretching mechanism, consisting of a bodyprovided with means for engaging the leather to hold it and having in rear thereof a slot concaved in the direction of the leather-engaging means, and a device adapted to engage in said slot and thereby pivotally connect the body to the stretching mechanism, substantially as set forth.

3. A leather-holder for a stretching-machine, comprising a body provided on its front portion with means for engaging the leather and in its rear portion with a slot concaved toward the leather-engaging means, and a coupling device loosely pivoted thereto in such slot and permitting said body to turn freely in lateral direction with respect to the coupling device under tension, the coupling device having means for making adjustable connection with a stretching-machine, substantially as set forth.

4. A leather-holder for a stretching-machine,comprisiug a body provided with means for engaging the leather, and a coupling device loosely connected thereto and permitting free swinging movement and lateral self-adjustment of said body with respect to the coupling device under tension, and means for adj ustably connecting the coupling device to a part of the stretching mechanism, substantially as set forth.

5. A leather-holder for a stretching mechanism, consisting of a body provided with tines for piercing the leather to hold it, in combination with a device for pivotally connecting the holder to a part of the stretching mechanism, said holder being provided with means for varying the point of its pivotal connection to the connecting device conformably to the direction of tension exerted upon the portion of leather engaged, substantially as set forth.

6. Ina leather-stretching machine, the combination with a stretcher-head, of an independent leather-holder comprising a body provided with means for engaging the leather and having a slot concaved toward the leatherengaging means, and an inflexible coupling device loosely pivoted to such body in such slot and permitting it to turn freely thereon and adjust itself laterally with respect thereto under tension, and means whereby the coupling device may be adjusted laterally and longitudinally upon and connected to the stretcher-head, substantially as set forth.

7. In aleather-stretching machine, the combination with a stretcher-frame, stretcherheads, and means for operating one of the heads, of a series of independent leather-holders adapted to engage marginalportions of j the end of a body of leather at different angles thereto and having slots concaved toward their leather-engaging means, a corresponding series of inflexible coupling devices to which the holders are loosely pivoted by 6 means of such slots to adapt them to swing freely and adj ust themselves in lateral direction under tension, and means provided on the stretcher-head and coupling devices permitting the latter to be adjusted to positions parallel with one another and for connecting themto the head, substantially as set forth.

8. In aleather-stretching machine, the combination with a stretcher-head, of a series of leather-holders having leather-engaging means on their front portions and in rear thereof slots curved in the direction of the leather-engaging means, a corresponding series of coupling devices adapted to engage in such slots and thereby pivotally connect the holders, and means for adjustablyconnecting the coupling-bars to the stretcher-head, substantially as set forth.

9. Aleather-holder for a stretching mechanism,consisting of a body provided on its JOHN CALDWELL.

In presence of-- P. H. GuNoKEL, M. F. HARRISON. 

